Refrigerating apparatus



E A. W. JEFFERIES.

REFRIGERATING APPARATUS.

APPLICATION man l AN.2l, 1919.

Rue nil-0 Patented May 24, 1921.

%- Z WW- UNITED STATES PATENT OFFICE.

EBENEZER A. VT. JEFFERIES, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO JEFFERIES-NORTON CORPORATION, OF WORCESTER, MASSACHUSETTS, A

CORPORATION OF DELAWARE.

REFRTGERATING APPARATUS.

Original application filed January 26,

To all whom it may concern:

Be it known that I, EBENEZER' A. W. JEFFERIEs, a citizen of the United States, residing at Worcester, in the county of Worcester and Commonwealth of Massachusetts, have invented new and useful Improvements in Refrigerating Apparatus, of which the following, taken in connection with the accompanying drawings, is a specition may be utilized for the purposeof liquefying, in whole or in part, the gaseous working fluid, and if desired this liquefaction, if the gas be a mixed gas, maybe employed in connection with suitable distillation agencies to effect the separation of the gas into its constituent elements. More over, as will be shown, the invention may with advantage be used for the cheap and eflicient production. of power in a form available for the production of useful work.

The present-invention is chiefly concerned with the recovery of power from the gases which are liquefied, as described in my aforesaidv patent. The power thus recovered. may be utilized in driving or assisting in driving the devices which are used for the initial compression of the gas, whereby a marked increase in efficiency and fuel economy, over other systems of this character now in'use, is attained. Other ob ects and advantages will appear from the followin description of the invention, reference Eeing had in this connection to the Specification of Letters Patent.

ance with the invention, for carryin Patented May- 24, 1921;

1915, Serial No. 4,536. Divided and this application filed January 21, 1918. Serial No. 212,862.

accompanying drawings, wherein the single figure 1s a diagrammatic representation of one arrangement of apparatus in accordout the process described in my aforesai patent. It is to-be'understood, however, that my invention is not in any way confined to the herein described, or any other particular arrangement of apparatus, nor to'the hereln described methods of operating the same, except in so far as specified in the annexed cla1ms; the drawings and description being illustrative mere y of one way of utilizing the broadly new principles of the invention.

As heretofore practised, systems of this class involving the li uefaction of gases have been characterizdfl by the release of the condensed fluid from pressure, thereby permitting spontaneous reevaporation of said condensed fluid, with a resulting high refrigerative effect during such reevaporation. The present invention differs essentially from such prior systems, in that the condensed fluid instead of being released from pressure, is either placed under additional pressure or suflicient pressure is maintained upon it so that the gas subsequently evaporated therefrom possesses the capability of absorbing heat usefully, thereb ac- I quiring considerably morethan enoug energy, when properly applied, to counterbalance the diminished refrigerative efli'ect during reevaporation.

The application of this principle for the attainment of the objects hereinbefore mentioned is illustrated by way of example in the apparatus of the accompanying drawing, wherein is shown, diagrammatically, a compressor 1, for compressing the gas as a preliminary to its liquefaction, as hereinafter described. The compressed gas is cooled by any suitable cooling device 2, as

for instance a water cooler, which extracts the heat of compression therefrom. From the cooling device 2 the gas is led to a pas sage 3 of a heat interchanger, the latter being designated as a whole by the numeral 4:. 'At the cold end of said heat interchanger the passage 3 terminates in a receptacle 5, which serves as a container for the gas after its liquefaction by the action of the interchanger. There is no escape for the liquid from the container 5 to the re turn circuit of the system except through a pump 6, which delivers the liquid into said return circuit through a refrigerating coil 7, at a pressure higher than the pressure in the passage 3, it being understood that in common with other refrigeration systems of this class, my invention contemplates the continuous liquefaction of the cooled compressed gas while traversing the passage of the heat exchanger 4, to replenish the .sup ly of liquid in the container 5, as fast as t e same is pumped out.

The fluid leaving the coil 7 enters a passage 8 forming another part of said heat exchanger 4, wherein it .is evaporated and has its temperature raised by interchange of heat with the gas in the passage 3 coming in from the compressor 1. The pressure prevailing in passage 8 and coil 7 is obviously due to the resistance imposed against outflow of vapor from the upper end of said passage; in forcing liquid into the coil 7, the pump 6 must put it under suflicient ressure to overcome the pressure thus maintained in passage 8, which, as above stated, is higher than the pressure prevailing in passage 3. The heat exchange between the fluids in passages .3 and 8, in a manner similar to that well-known in apparatus of this character, entails the discharge of high pressure fluid from the top or warm end of passage 8 at substantially the temperature of the gas entering the interchanger at the top or warm end of passage 3; the substantial equalization of temperatures at any given level by heat interchange between the two passages 3 and 8, is contemplated, and in common with other apparatus of this character, the temperatures are lower, the lower the level reached in said interchanger. The passage 8 communicates with a heating device 9, wherein the whole or a portion of the gas evaporated from the liquid leaving the pump 6, has its temperature further increased, prior to its use in a hot expansion engine or motor 10, which may be operatively connected to drive the compressor 1. Part of the gas passing through the exchanger in passage 3 may be used in a cold expansion or refrigerating engine 11, which may be operatively connected to the compressor 1 and motor 10. Said engine 11 exhausts into the cold end of a passage 12 which forms a third part of the heat exchanger 4. Ifpreferred, that portion of the gas used in said refrigerating engine 11 may be taken from the passage 8, after reevaporbroken lines denote the presence of liquefied gas in container 5 and c-oil'7,i't will be clear that the cold expansion engine 11, passage 12, and their several interconnections constitute an external cooling agency, the provision of which, in one form or another, is

requisite to the liquefaction of the gas traversing passage 3 from the compressor 1 to the container 5. As set forth above, the increase in pressure upon the liquid effected by the pump 6, imparts to the outgoing gas evaporated from such liquid, the ability to absorb heat usefully and thus to attain more energy than is possessed by the same quantity of gas brought into the exchanger 4 at the original pressure by passage 3.

The amount which the pressure is increased by pump 6 governs the amount of available energy contained in the gas leaving the exchanger on its way to the heater 9. The cold expansion engine 11 also contributes some energy, and the balance, to make up the total-required to operate the system, may be supplied, in part at least, by the addition of heat to the outgoing gas, at the increased pressure, in the heater 9, causlarge portion of the power required for operating the entire system.

It will be seen, therefore,that the invention contemplates an increase, rather than a decrease in the pressure of the liquefied gas; an evaporation of the same during its return through the exchanger under such increased pressure; the addition of heat to said products of evaporation by external means, still further increasing its available energy over that absorbed in compressing the incoming gas; and the recovery of power therefrom to perform useful work. The heat required for vaporizing the liquid, so placed under increased pressure, and for raising the temperature of the vapor in the exchanger is derivedfrom an interchange of heat with the fluid which is passing through earlier stages in the process, and from heat leaking into the exchanger from the atmosphere; the surplus heat required to raise the temperature of the said vapor above that of said incoming fluid, in order still further to increase the available energy contained in said vapor over that absorbed in compression of said incoming fluid, is derived from exterior sources, such as steam, combustible fuel, or

waste heat. ation at the increased pressure, instead .of-

I am aware that the system herein deing the hot expansion motor 10 to deliver a I g faction of the scribed can be most usefully employed only with fluids whose boiling points are belowpable of being applied, if desired, to theproduction of additional refrigeration and to operating the system in a more eflicient manner than heretofore.

Although I have described the invention as involving an increase on the pressure on the liquefied fluid before reevaporation for the purpose of ultimate power economy, yet it will be obvious that the same purpose may be accomplished, in less degree, if the pressure is merely sustained instead of, being released in the usual manner; or, the pressure may even be reduced and still carry out the purpose of this invention by retaining suffi'cient pressure to permit of absorbing heat usefully for the production or recovery of power. Y

It is to be understood that the invention, as herein described, does not of necessity entail either the complete or the absolute liqueaseous working fluid, and that the terms liquefaction, liquid and liquefied as used herein and inthe appended claims apply as well to a condition of the fluid where 1n density and temperature it substantially approaches the liquid state. In such a condition said fluid is susceptible to a pressure increase by the expenditure of an almost negligible amount of power. which, together with the power required for initial compression 1s largely recoverable in the efficient manner hereinbefore set forth.

In the application of the foregoing new principles, which differ radically and essentially from the principles underlying previous systems of this class, it is to be understood that my invention is in no sense limited to equivalents of the apparatus shown, said showing being wholly diagrammatic and illustrative and adopted solely for the purpose of simplifying the explanation of said broadly new principles.

I claim:

1. The combination with means for lique- V fying a working flu1d which is gaseous in its free state, ofmeans for sustaining the pressure on the evaporate from said liquid, means for circulating said evaporate in heat exchanging relation to the gaseous fluid about to undergo liquefaction, and means for thereafter expanding said evaporate, to furnish ower.

2. n a system of the character described, means for liquefying a aseous working fluid, comprising a reverse 0w interchanger,

and means for sustaining the pressure of the fluid in the outgoing side of said interchan er.

3. na system of the character described, means for liquefying a gaseous working fluid, comprisin a reverse flow .interchanger, means or sustaining the pressure of the fluid in the outgoing sideof said in-.

terchanger and a motor for the expansion of the said outgoing fluid under pressure, to produce useful work. p

4. In a system of the character described,

means fOrdiquefying' a gaseous working fluid, comprisin a reverse flow interchanger, means or sustaining the pressure of the fluid in the outgoing side of said interchanger means for heating the evaporate of said outgoing fluid under pressure, and a motor for the expansion of said heated evaporate.

5. The combination with means for liquefying a working fluid which is gaseous in its free state, of means for increasing the pressure on the evaporate from said liquid,

means for circulating said evaporate in heat exchanging relation to the gaseous fluid about to undergo liquefaction, and means for thereafter expanding said evaporate, to furnish power.

6. In apparatus of the character described, the combination with means for progressively liquefying a gaseous working fluid, of means for sustainlng or increasing the pressure on the liquefied portion of said fluid, and means for maintaining said pres-- sure on the evaporate from said liquefied portion during its circulation, in heat exchanging relation to the gaseous fluid abou to undergo-liquefaction. v 7. In apparatus of the character described, the combination with means for progressively li uefying a gaseous working fluid, of means or sustaining or increasing the pressure on the liquefied ortion of said fluid, and means for circulatingthe evaporate from said liquefied portion, under said pressure, in heat exchanging relation to the gaseous working fluid which Is about to undergo liquefactlon.

8. In apparatus of the character described, the combination with means for progressivel liquefying a gaseous working fluid, 0 means for maintainin an increased pressure on the evaporate rom the the gaseous working fluid about to undergo liquefaction, means for supplying external heat to said evaporate, and means for expanding said heated evaporate, to furnish sufficient pressure aipon the fluid in the power. liquid state, to enable the evaporate there- 10 9. In apparatus of the character set forth, from tolabsorb external heat usefully.

the combination with a reverse flow heat Dated this 17th day of Januar 1918.

interehanger, of refrigerating means for EBENEZER A. W. JEFF RIES. promoting the liquefaction of a gaseous WVitnesses: working fluid in the cold end of said in- NELLIE WHALEN,

terchanger, and means for maintaining a PENELOPE COMBERBACH. 

